1. Field of the Invention
The present invention relates to rotary drive mechanism for a horse exerciser such as a hot-walker or a treadmill.
2. Prior Art
In a known radial arm rotary mechanical hot-walker, a two-speed motor rotates an upright shaft carrying the radially projecting arms to which horses are tethered, the object being to exercise horses at a trot when the motor is operating at its high speed and to cool out horses at a walk when the motor is operating at its low speed.
A problem with such a known hot-walker is that only either of two constant speeds may be selected. In practice, the optimum walking speed for cooling out horses until they stop sweating and relax varies from horse to horse. Similarly, the preferred exercising speed varies in accordance with the size and condition of a horse.
Another problem with such a known hot-walker is that on start-up a sharp jerk is applied to the horse which may cause the horse to shy and refuse to be led, resulting in damage to the hot-walker or injury to the horse.
Another problem with such a known hot-walker is that, for either operating speed, the maximum torque transferrable by the motor to the hot-walker shaft is constant, though horses react differently to different tensions applied to their lead straps.
Because of these problems, it is necessary to train horses to accept being cooled out or exercised by use of the known hot-walker. Until now, horses which were not well trained still had to be cooled out or exercised by an attendant.